The Epidemiology/Statistics: Research Operations Core is responsible for support and consultation in the following areas: 1) identification and characterization of populations for the proposed behavioral interventions, 2) measurement and data collection, 3) data base management, and 4) quantitative analyses. The core staff will use its collective expertise to anticipate the data collection requirements of the proposed projects to propose methods, evaluate their relative efficiencies, and facilitate implementation of the optimal methods. As a whole, these projects constitute a marked expansion in the number of individuals from whom data will be collected on a periodic basis in comparison to the present CCSP. The experience of the core staff will allow us to schedule, disseminate materials and reinforce recommended behaviors in an efficient and timely manner, incorporating findings of the screens where appropriate. In addition, appropriate verification of behaviors and periodic followups for data collection will require quality control/quality assurance. Needs assessments, which this core staff will perform regularly, will provide support for commitment of resources (e.g., computer systems) to address these components of any and all of the proposed projects. The sharing of the core staff expertise in data management will facilitate selection and implementation of optimal approaches for the following: file creation, modifications (edit/update), determining storage requirements (size, regularity of acquisition, medium) documentation and archiving. Throughout the execution of the proposed program projects, the core staff will provide for the timely acquisition, processing and quality control/quality assurance of all data collected to facilitate the management of each project. To realize the overall efficiencies of collaborative research, it is essential that the core staff has time to review and adapt materials and methods, and the opportunity to create standards and procedures applicable across projects. This pooling of professional talent will result in marked savings. A major commitment on the part of core staff to one or more projects provides the basis for developing and maintaining the lines of communication and authority required to implement the proposed standards and procedures.